The mission
D-Sat is a three-unit CubeSat designed, built, and operated by D-Orbit. The CubeSat was launched on June 23rd, 2017 into a 500 km sun-synchronous orbit, with the goal to validate D-Orbit Decommissioning Device (D3) in space.
D3 is a smart propulsion system optimized for decommissioning maneuvers. D3 is a technology we have designed, developed, and ground-tested for about five years. As with other space technology, the final step is to test a prototype in space and collect performance data that enable our engineers to apply the final touches to the production line.
During the mission design phase, we partnered with several institutions to include three experiments that were performed throughout the mission’s lifetime. In tune with our philosophy, all three experiments had a social impact.
the experiments
Throughout its mission, D-Sat performed three experiments: SatAlert, Debris Collision Alerting System (DeCas), and Atmosphere Analyzer.
SatAlert, designed in collaboration between D-Orbit and the National Inter-University Consortium for Telecommunications (CNIT), University of Florence Research Unit, was an in-orbit validation of the Multiple Alert Message Encapsulation (MAMES) protocol, defined by ETSI (European Telecommunications Standards Institute).
The experiment proved the viability of the encapsulation process, the transmission of MAMES over the space segment, and the reception and decoding by a portable Software Defined Radio User Terminal (SDR-UT).
All the system components performed as expected, validating the whole alert messaging chain from the alert generation to the MAMES reception, including D-Sat’s onboard processing and broadcasting capability, the SDR-UT reception, and the web-based machine-to-machine communication mechanisms for data exchange. To validate the main features of MAMES, ground station operators generated and uploaded different types of MAMES messages.
The success of the SatAlert Experiment is the first step towards a wider implementation and adoption of the MAMES protocol.
These emergency scenarios are becoming increasingly common, given the tight correlation between climate change and extreme weather conditions like hurricanes, wildfires, tornadoes, extreme rainfalls, and floods, and for this reason SatAlert may help saving thousands of lives.
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SCIENTIFIC AMERICAN: Is There a Strong Link between Extreme Weather Events and Climate Change?
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EPA: Understanding the Link Between Climate Change and Extreme Weather
DeCAS (Debris Collision Alerting System), developed by Aviosonic Space Tech, is a patented system able to determine the dynamics of the debris footprint area associated to the re-entry of the hosting satellite.
Upon re-entry of the hosting spacecraft, DeCAS survives the break-up phase and broadcasts the debris footprint dynamics forecast to civil protection agencies. In a real-world scenario, this information would be processed on ground and then transmitted in real-time to airplanes flying over that zone through the Air Traffic Control Center, and to the populated areas below through national public safety agencies.
To validate the system, D-Sat’s ground operators have submitted 83 messages simulating uncontrolled re-entry. DeCAS was able to process in real-time more than 98% of these messages, which were afterwards sent to CNIT for the encapsulation into MAMES protocol messages and for the consecutive upload. Ten of these alerts have successfully completed the entire process, simulating a DeCAS satellite broadcast service. Thanks to a collaboration with Ponti Institute and ARI of Gallarate, where Aviosonic had installed its ground station, all DeCAS messages have been received, along with more than 14 hours of D-Sat broadcasts, validating the whole system architecture.
Atmosphere Analyzer was a data collection experiment aimed at collecting in-situ atmospheric data from the lower ionosphere during the re-entry maneuver. The region between 80 km and 150 km is the least studied region of the atmosphere because it can’t be reached by satellites or stratospheric balloons. While in orbit, D-Sat has performed a number of simulations, validating this innovative approach for an in-situ data collection.